Mazda6

Corporate average fuel economy (CAFE) represents the fleet average for automotive manufacturers nationwide. The federal government has mandated that automakers reach a 54.5 mpg threshold by 2025 with incremental increases between now and then.

To obtain ever higher fuel economy numbers, car manufacturers are downsizing models, shifting from heavier body-on-frame to lighter unibody construction, making use of smaller engines and adding a few extra gears to transmissions. Lighter weight materials, such as carbon fiber and aluminum are also being added, making it possible for cars to achieve higher year-over-year fuel economy numbers.

For the 2014 model year several vehicles are offering improved fuel economy over earlier models. Sometimes the changes are more profound as in a generational product change to more subtle changes made to engine performance.

2014 Toyota Corolla.

Toyota Corolla

The best selling vehicle in the world is the Toyota Corolla although some contend that the Ford Focus now outsell’s this iconic compact car. For 2014 the Corolla is all-new with a fresh face and a slightly longer wheelbase.

While the Corolla comes in a bit larger, it also is more efficient. The base 1.8-liter four cylinder engine returns and is now available with an optional “Eco” mode. As outfitted, this model is rated 30 mpg in the city and 42 mpg on the highway, up from its previous 27 mpg around town and 34 mpg on the highway. This engine is now paired with a continuously variable transmission.

Chevrolet Malibu

Chevrolet has gotten clobbered in the midsize sedan segment despite serving up an all-new model for 2013. Its design has been criticized for not being bold enough, forcing GM to hasten its mid-cycle refresh by several years.

The refreshed Malibu now comes standard equipped with smart-stop technology what shuts off the engine when it is at idle such as at a traffic light. That move raises its fuel economy to 25 mpg in the city and 36 mpg on the highway, up from 22 mpg in the city and 34 mpg on the highway for the 2013 edition.

2014 Mazda6.

Mazda6

The 2014 Mazda6 has been on the market for some time now. It is an all-new model employing the brand’s SKYACTIV technologies (i.e., more fuel efficient engines and transmissions, lighter weight materials) to deliver a much more fuel efficient model.

Powered by a 2.5-liter four cylinder engine paired with a semiautomatic six-speed transmission, Mazda’s midsize sedan is rated as high as 28 mpg in the city and 40 mpg on the highway. To achieve its segment leading numbers, customers will need to choose the top-of-the-line Grand Touring 2.5L with an automatic transmission and technology package. It represents a huge jump in fuel economy for a vehicle previously rated no better than 21 mpg in the city and 30 mpg on the highway.

GMC Sierra

At first glance, the three engines found in the 2014 GMC Sierra and sister Chevrolet Silverado seem to be the same as those offered in 2013 and earlier years. However, all three are now third generation engines, sporting the EcoTec3 label. The new engines feature several changes including what is most apparent on the 5.3-liter V-8: cylinder deactivation, variable valve timing and direct injection.

The rear-wheel drive GMC Sierra equipped with the small block V-8 is now rated at 16 mpg in the city and 23 mpg on the highway. That is up from 15 mpg in the city and 21 mpg on the highway in 2013. Importantly, the Sierra and Silverado beats competing models from Ford and Ram including Ford’s available V-6 EcoBoost engine.

2014 Mitsubishi Mirage.

Mitsubishi Mirage

The Mitsubishi Mirage gets an honorable mention here. Because the model is all new and does not replace a previously offered vehicle, you cannot compare it with itself. The Mirage name is not new — it was used on a compact car in the 1990s and the new model is a subcompact.

Choose a 2014 Mitsubishi Mirage and pair its 1.2-liter four cylinder engine with a continuously variable transmission and your vehicle is rated at 37 mpg in the city and 44 mpg on the highway. That is best for a small car that is neither a hybrid nor a diesel. Mitsubishi credits a 0.28 coefficient of drag, variable valve engine timing and electronic power steering in helping the Mirage achieve its lofty mpg threshold.

Fuel Economy Considerations

If you were to survey the entire automotive industry over the past several years it is apparent that car manufacturers have been making incremental changes year over year. Expect to see more diesel-powered cars, hybrid electric vehicles and electric vehicles enter the mix in a bid to raise CAFE. Most consumers, however, will continue to buy conventionally powered vehicles, but those models will come in lighter and more efficient than the ones currently available.

It is quite a feat when any vehicle makes 40 mpg on the highway. However, it is a much more noticeable accomplishment when a midsize sedan reaches that threshold and does so without a hybrid powertrain or a diesel engine under the hood. That’s exactly what Mazda has done with one version of its Mazda6 sedan, a five-passenger front-wheel drive model that has raised the fuel mileage bar.

i-ELOOP Technology

Not every 2014 Mazda6 model makes 40 mpg, but those that are equipped with its i-ELOOP brake energy regeneration system do. Regenerative braking is usually a feature of hybrid models, but Mazda has outfitted certain models with i-ELOOP.

The Mazda i-ELOOP system does what regenerative brake systems are designed to do: harness kinetic energy and reuse it as electricity. That energy is obtained whenever the sedan decelerates and is stored for later use in a variable valve alternator. Unlike conventional alternators that charge to around 12 volts, the i-ELOOP alternator stores from 12 to 25 volts.

Essentially, i-ELOOP is a three-function system that regenerates, stores and uses kinetic energy to power the headlamps, turn signals, brake lights, the audio system and other electrical components. In doing so, energy that would normally be accessed from the engine is not used, thereby increasing fuel mileage by up to 10 percent.

“Mazda is again changing the game of automotive engineering, this time making fuel efficiency not seem as a compromise but a true complementary feature as part of the complete vehicle package,” said Jim O’Sullivan, president and CEO, MNAO. “With the addition of i-ELOOP, the 2014 Mazda6 will achieve the best mileage for a non-hybrid midsize sedan. But fuel economy isn’t the sole focus of our engineering and design teams, as being a leader in dynamics, design and safety create a win-win for the company and consumers.”

Mazda6 Grand Touring Edition

Initially, i-ELOOP will be offered only with Grand Touring models as part of a GT Technology Package. The Mazda6 Grand Touring retails from $29,695 and the technology package adds $2,080 to that price. Besides i-ELOOP, the package includes adaptive cruise control, high beam control, a lane departure warning system, forward obstruction warning, active grille shutters and a sport mode button.

The two mpg mileage gain may not be worth the extra price consumers would pay for a full-loaded Mazda6. Indeed, the 2014 Mazda6 Sport when equipped with an automatic transmission, retails from $22,495 or about $9,000 less than an i-ELOOP-equipped model. For $24,495, the Mazda6 Touring edition brings in dual-zone climate control, larger wheels, a power drivers’ seat, rear heated seats, a touchscreen display, HD radio and select safety systems.

If you want navigation and a Bose sound system, the $29,945 Grand Touring edition provides those features while still delivering 38 mpg on the highway. So, to achieve the 40 mpg threshold you need to pay an extra $2,080, a price that also gets you additional safety features. Fully loaded, a 2014 Mazda6 pushes into luxury sedan territory, virtually matching the $33,095 starting price for the 2014 Cadillac ATS sedan. Advanced technologies come at a price, but will Mazda6 shoppers bite? That remains to be seen.

Midsize Model Class

With its new 40 mpg rating, the 2014 Mazda6 inches ahead of the Nissan Altima, rated at 27 mpg in the city and 38 mpg on the highway. Competing midsize models that also deliver excellent fuel economy include a Ford Fusion model rated at 25 mpg city and 37 mpg on the highway, the Toyota Camry rated at 25 mpg around town and 35 mpg on the highway and the Kia Optima rated as high as 24 mpg in the city and 35 mpg on the highway.

There are also several hybrid models that approach the Mazda6′s price, while delivering better overall fuel economy and a suite of amenities. Auto Trends recently tested the Hyundai Sonata Hybrid Limited, a model that is rated at 36 mpg in the city, 40 mpg on the highway and is priced from $30,550.